Television service has recently started being delivered to end-users over the Internet Protocol (IP) network. IP television (IPTV) is oftentimes delivered by use of an IP multimedia service (IMS) network. Some of the many advantages of IPTV over traditional broadcast television comprise the possibility to offer video on demand (VOD), using picture-in-picture to peek into a second channel while watching a program on a first channel, pausing, rewinding and restarting a program, and the like.
In the IMS architecture, there is an IMS gateway linking various IP-enabled devices in a household to the external IMS network. The gateway essentially acts as a user agent (UA) for interfacing between service providers in the IMS network and end-user devices. A variety of services can be provided to users logged onto the IMS network, through the IMS gateway. The nature of IPTV IMS services is such that end-users must log in or register to the IMS network, though the gateway, before getting access to services. The gateway is able to relate signaling between the IMS network and the devices connected thereto by keeping identities of those devices in memory.
In a household, a same IPTV terminal function (ITF), also called set-top box (STB), may be shared by more than one user. For example, a first user may be recording a movie on a digital recorder while a second user may be watching a television program on a TV set. As a result, two or more users of a same ITF may be logged in or registered at the same time. However, while one user may be actively watching a television program, another user might be “inactive” in the sense that, whether or not the TV is powered on, the person is not currently watching the movie, which is intended to been seen later on.
IPTV and IMS networks are such that there can be multiple applications running in the background. Consequently, all events associated with users that are not actively present, but registered in the network, may end up being presented to other active users of a same household, leading to much confusion.
As an example of a problem found in the prior art, user A in a household has first logged in and programmed a network personal video recording to start two hours later. User A has logged out and is thus not currently active. User B in the same household logs in to watch a television program and is now an active user. Two hours later, the network personal video recording application starts executing in the background. That application registers the user A to the IMS network, on his behalf, so it can start the recording. This step of registering the inactive user A is essential for compliance to the IMS network.
While the user A is not active, in the sense that he is not at that time watching a television screen, he is however registered as far as the IMS network is concerned. Once the user A is registered, he can receive any network event intended for him, even though the user A is indeed not actively watching the television screen. Such network events, because they are received on the ITF shared by both users A and B, are displayed on the television screen currently being watched by user B. One possible example of network event, wrongly displayed on the television screen of user B, may be a tariff indication for recording the movie requested by the user A. This may be confusing for the user B. Moreover, if a network event requires an acknowledgement from the user A, the user B may refrain from providing the acknowledgement, which may cause the network to repeat the network event, thereby causing useless traffic leading to congestion in the network. Alternatively, the user B might provide an acknowledgement that is not what the user A might have desired, for example refusing the indicated tariff and thereby cancelling the recording.
Currently it is not possible, without adding significant complexity in the ITF, to hide undesirable effects resulting from messages intended for inactive users that arrive to the ITF while other users are active.